


Poor Unfortunate Soul

by astudyinfic



Category: Shadowhunters (TV)
Genre: Anal Sex, Body Horror, Consentacles, Deal with a Devil, LITERALLY, M/M, Not Beta Read, Porn With Plot, Tentacles, Topping from the Bottom
Language: English
Status: Completed
Published: 2019-10-11
Updated: 2019-10-11
Packaged: 2020-12-09 05:03:25
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,481
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20989307
Author URL: https://archiveofourown.org/users/astudyinfic/pseuds/astudyinfic
Summary: Every nephilim knows not to make a deal with the devil.  But no matter the cost, Alec didn't regret it.  Not when it brought Magnus back to him (and a new dimension to their relationship).





	Poor Unfortunate Soul

**Author's Note:**

> Today's tentacle-tober prompt is 'tentacle porn' and this week is 'came back wrong' for the frightening-fic-fest so why not combine them? Enjoy.

Never make a deal with the devil.

Every nephilim knew it. Every nephilim knew that nothing good could come from it.

But for Magnus, Alec was willing to do anything - sacrifice anything - to get his magic back. Magnus wasn’t Magnus without it, and while he tried to pretend otherwise, Alec could see the pain in his lover’s eyes when Magnus thought he wasn’t looking.

And so he’d gone to Edom to make a deal with the devil’s favorite brother. Asmodeus took great joy in negotiating with Alec and for a while, Alec didn’t know if the ruler of Edom would agree, even after all of this. But in the end, Asmodeus agreed to return Magnus’s magic and immortality.

“You know what you are doing, don’t you?” Asmodeus asked, walking around Alec, sizing him up. “You know that making a deal with me will leave a mark on you, Shadowhunter.”

“I already told you I agree to your terms. Just do it and stop talking.” He was worse than Simon when it came to talking without actually saying anything useful. Alec accepted that there was no turning back after this. He would deal with the consequences, as long as it meant Magnus got his power back.

The pain had been unbelievable and Alec struggled to stay conscious under the brunt of it. He couldn’t let Asmodeus have any more power than he’d already granted, so he would look the Prince of Hell in the eye as Asmodeus’s own magic flowed over him. Eventually, he couldn’t keep his eyes open any longer and he saw the victorious grin on his lover’s father and Alec succumbed.

He woke later in the loft, Magnus standing over him, eyes sparking with anger and concern. Alec focused entirely on him, doing his best to ignore the anger and instead choosing to smile at just how he relieved he was to see those cat-eyes, however upset they might be. It meant Asmodeus kept up his end of the bargain and Magnus was restored.

“Alexander.” Magnus’s voice was eerily calm and Alec had no doubt that they would have words about what he did. Not that he regretted it. Whatever Asmodeus did to him was worth it if it meant Magnus was okay. “What did you do?”

He could have lied, could have told Magnus he didn’t know how he got his magic back or any other number of small fibs that would have kept Magnus from jumping down his throat. But considering the way Magnus glared and the emotionless tone of his question, Alec knew. Magnus already knew the answer to his question.

“I made a deal with your father. You and I both know you would have gone down there eventually and paid whatever price he wanted. This way, you didn’t have to.” Alec reached out and took Magnus’s hands in both of his. “I only wanted what was best for you.”

“You probably should have consulted me first.” The barely restrained anger in his voice chilled Alec but he knew Magnus would forgive him eventually.

Alec brushed some hair out of his eyes and stared up at him, willing Magnus to see how sincere he was. But Magnus’s eyes narrowed even more and Alec froze, trying to figure out what he’d done to warrant that sort of ire. All he did was brush his hair out of his face.

While both of his hands were still laced with Magnus’s.

He looked down at himself and swallowed heavily. “Oh.”

Well, Asmodeus did warn him that it would leave a mark. Alec simply didn’t realize just how true that would be.

It was taking some getting used to. Alec didn’t know why he thought it would be any different. One didn’t grow a few extra appendages overnight and just move on as if nothing happened. He couldn’t forget the anger in Magnus’s cat-eyes when he looked at the aftermath of Asmodeus’s spell. Alec took it upon himself to make a deal to get Magnus’s magic back and the result was Magnus was a full warlock, immortal and powerful once more. And Alec...had extra appendages.

Four extra appendages.

The anger that Magnus had when looking at him was soon replaced by something else, however. A hunger that Alec never saw before. He didn’t understand it and didn’t have time to figure it out. He was still coming to terms with the situation. He hadn’t been back to the Institute since returning from Edom. How was he supposed to explain what happened? Izzy and Jace would probably understand after a while. His mother would be furious that he put his own life on the line like that. Max would probably declare it ‘cool’. But Alec knew no matter how much his family supported him, his life as he knew it was over.

No Shadowhunter could make a deal with the Prince of Hell and expect to remain a member of the Clave.

Particularly when he had what amounted to a warlock mark these days. Alec took to not wearing a shirt around the house because it was too hard to put one on when he had four more limbs that needed a place to go. He kept them tucked behind him as much as possible, never touching Magnus with them and shrinking away whenever there was a chance his lover might even brush up against them.

It would have been one thing if he’d just grown four more arms. Strange but useful. In quieter moments, Alec thought about being able to use two bows at a time if that was what happened. Instead, Alec had four tentacles, two pair along his sides. The purple, scaly limbs didn’t unnerve him quite the way they did the first day he had them but it still shocked him every time he looked in a mirror. Once he recovered from the shock, Alec spent hours over the next few days learning how to use them, how to keep them from knocking everything over. He was a Shadowhunter, in complete control of his body at all times. These new limbs would fall in line sooner or later.

But it wasn’t happening soon enough. He woke up one morning curled around his boyfriend, content in that sleepy way that left one briefly oblivious to the trials and tribulations of the world. Magnus shifted against him and Alec didn’t even bother hiding his interest in having their bodies pressed as close as possible. Physical intimacy had been lacking since his transformation because Alec didn’t want to see the horror on Magnus’s face when he accidentally brushed up against one of the tentacles now growing from Alec’s sides. But in his sleepy state, Alec didn’t think about that, only pulled his lover closer; hands pressed to his chest, other limbs skimming over Magnus’s sides, stomach, and thighs.

It didn’t take long for Alec to realize what was happening and he tried to pull back, an apology on the tip of his tongue. To his surprise, however, Magnus gripped the top of his arms, keeping Alec close. “No,” Magnus whispered, voice husky and dark, something Alec doubted had anything to do with sleep. “Don’t stop.” Magnus’s interest in what was happening was obvious, hard against Alec’s hip.

In the weeks since making the deal, Alec never expected this, though maybe he should have. Magnus never looked at him with revulsion the way Alec expected. Magnus was a better person than anyone Alec ever knew. And if he didn’t mind Alec’s extra appendages touching him, well, then... It had been a long time since they’d been together like this. Alec wasn’t going to say no now that he knew Magnus really was okay with it.

So instead of pushing him away, Alec wrapped his arms tighter and kissed Magnus with all the love he felt for him, all the frustration that had been building in him since the change, and all the desire that Alec wanted to let loose.

Moaning, Magnus magicked away their clothes almost immediately, something that thrilled Alec. He only had on thin pajama pants and Magnus didn’t have much either but even a thin barrier like that was too much for him right now. He’d deprived himself of his lover’s touch for too long and now he needed Magnus like breathing.

“Touch me,” Magnus breathed out against Alec’s lips and Alec ran his hands down Magnus’s chest, wanting to grip them both and bring them to completion. But Magnus pulled back and shook his head. “No. Not with your hands.”

It took Alec a moment to realize what Magnus was asking for but when he got it, his breath caught in his throat. “Oh, you mean...?” He glanced down at the tentacles, then back at Magnus. “Are you sure?”

"There are very few things in my life that I have been surer of, Alexander. Please." Looking down at his lover, naked and wanting, his cock hard and leaking, Alec accepted that this was something Magnus really wanted. And if he was honest, he wanted it too.

He started slowly, running his newest appendages down Magnus's chest, circling his nipples with the tips, causing Magnus to gasp and arch in pleasure. Seeing Magnus give himself over to the pleasure of Alec's body on his was a heady thing and Alec couldn't wait to see that for the rest of their lives together.

As he worked his way down Magnus's chest, Alec took a deep breath to center himself, bracing in case Magnus decided he didn't like this after all. Wrapping a tentacle around his lover's cock, giving a slow tentative stroke. Magnus gasped and cried out, magic flickering in his hands as he lost control of himself after such a gentle touch. It made Alec want to see what else he could do to bring Magnus to the highest point possible.

More confident, Alec began to stroke Magnus, using his arms to hold himself above his lover while his tentacles moved around and on him. With each stroke, Magnus cried out louder, sharper, and Alec could hardly hold back from touching himself, painfully turned on from just the sounds his lover made and the sight of him spread out like this.

He slowed his movements, not sure if this was all Magnus wanted and wanting to clarify before they went any further. "Do you want me to bring you off like this or...?" he asked, trailing off when he couldn't figure out how to end the question.

Magnus, however, knew exactly what Alec was asking, even if Alec didn't know himself. "I want to fuck you," Magnus said, looking Alec straight in the eyes. "I want to fuck you while you fuck me."

Alec's brow furrowed as he tried to figure out how that would work. Logistically, it didn't make sense. Until Magnus ran one hand up and down one of his tentacles and he finally understood. "Oh. You want me to fuck you with..."

Nodding, Magnus surged up and kissed Alec with all the passion he was feeling, throwing him off balance and knocking the Shadowhunter onto his back.

The cool force of Magnus's magic penetrated him, stretching and making him slick and ready. Magnus lined himself up and pushed into the hilt, only pausing once fully sheathed inside Alec. Alec took deep breaths to calm his racing heart. It had been weeks since they'd come together like this and the stretch was almost too painful. But he relished it, enjoying the feeling as it meant that he and Magnus were connected once more in the most intimate of ways.

But that wasn't what Magnus had asked for, not completely, and Alec tried to get his mind focused back on giving Magnus what he wanted instead of simply surrendering to the pleasure of Magnus moving inside him.

"I'm ready for you," Magnus told him, lips brushing against the pulse point on Alec's neck. "Please, darling, I need this. I need you."

Whatever argument Alec had against doing this vanished from his mind at Magnus's breathy request. He could see the need in his lover's eyes, the desire to do just what they'd discussed. If this was what Magnus wanted, Alec was going to give it to him.

His hands gripped Magnus's shoulders as his tentacles wrapped around him, holding Magnus close. "You're sure?" he asked one last time, desperately trying not to do the wrong thing.

Magnus growled and snapped his hips forward. "Yes, I'm sure, Alexander. Please..."

Alec nodded and slipped the tip of one of his tentacles into Magnus. He watched as his lover arched at the intrusion, the movement pushing him deeper into Alec who cried out in return. When Magnus pulled back, Alec penetrated him deeper, creating a feedback loop of pleasure as Magnus fucked Alec and then fucked himself on Alec's newest limbs.

He hadn't noticed until then just how sensitive the tentacles were but he could feel Magnus all around it, feel the tight, velvety heat that gripped him tight with every thrust. Each movement pushed him closer to the peak of pleasure, heat pooling in the pit of his stomach as Magnus rocked against him in absolute ecstasy.

Alec forgot all his concerns about his new body, all his concerns that Magnus was turned off by him and simply gave himself over to the pleasure of being with the man he loved. Alec wrapped one of his other tentacles around his own length, stroking him with every thrust of Magnus's hips, while he penetrated his lover with his own tentacle.

It wasn't long before Magnus stuttered and pressed himself as deep as possible, filling Alec with his release. Alec followed a few moments later, clenching around Magnus's softening length as he spilled between them. Slowly, Magnus pulled out of Alec and Alec pulled back from Magnus, leaving them both feeling open and empty. They lay on their backs, side by side, chests heaving as they tried to regain their breath. Alec didn’t even bother trying to keep the tentacles closest to Magnus from moving over to touch him.

“That was...” he started before realizing he didn’t have the words to describe it.

Magnus chuckled. “Yeah, it was.” Magnus traced a finger down one of the tentacles closest to him, causing it to curl possessively around his wrist.

Alec rolled his eyes as Magnus laughed. “I’m beginning to think they love you as much as I do.”

“Good.” That glint in Magnus’s eyes was back and Alec swallowed hard, knowing now that it portended good things. “Because I have so many things I want to do with all of you.”

Pulling Magnus close and wrapping him up in as many appendages as he could, Alec thought maybe, occasionally, something good did come out of making deals with the devil.

But he wasn’t going to make a habit of it.


End file.
